Tired Of Waiting For The Ambulance To Arrive With Your Trauma Patient?

When trauma patients are enroute to the hospital, accurate arrival times are crucial. If the patient arrives later than announced, the trauma team waits and wastes time. If the patient gets there early, it’s really a form of undertriage and they may not be able to immediately get the critical services they need. A Portland study noted that more than half of transport time estimates were off by at least 10 minutes, and over a quarter were wrong by 10 minutes or more! Surely there must be a way to predict transport time more accurately!

Harbor-UCLA Medical Center developed a simulation using transport data from a single Oregon county for an entire year. Their goal was to determine the factors that influenced transport time and develop a Google Maps application that would be more accurate than current estimates. Route mapping software was used, with inclusion of variables such as patient demographics, use of lights and siren, time of day, and weather. Individual variables that were statistically found to be insignificant were removed, one at a time, until the best model was derived.

Nearly 50,000 transports were analyzed to create the Google Maps application. Here’s what it looks like:


And here are the interesting findings:

  • Without a model, baseline accuracy was only 16% within 5 minutes of predicted
  • Transport times were longer during daytime and rush hour (gee!)
  • Shorter times occurred with use of lights and siren (gee whiz!)
  • Age, sex, wet roads, and trauma system entry had no effect on times
  • Use of the model within the Google Maps app increased accuracy to 73% within 5 minutes. Use of lights and siren boosted the accuracy to 78%

Bottom line: Yes, it is possible to enhance the accuracy of arrival predictions of your ambulances. This method should be adopted everywhere! Not only can it improve trauma team use and trauma patient treatment, it can improve ED resource usage for any incoming patient.

Rreference: Predicting Ambulance Time of Arrival to the Emergency Department Using Global Positioning System and Google Maps. Prehospital Emergency Care online first, doi:10.3109/ 10903127.2013.811562.

Stuff You Sterilize Other Stuff With May Not Be Sterile??

When one works in the trauma field, or medicine in general, we deal with the need for sterility all the time. We use equipment and devices that are sterile, and we administer drugs and fluids that are sterile. In surgery, we create sterile fields in which to use this sterile stuff.

In the past few years, we’ve come to the realization that the sterility we take for granted may not always be the case. There have been several cases of contaminated implanted hardware. And most recently, supposedly sterile injectable steroids were found to be contaminated with fungus, leading to several fatal cases of meningitis.

An article in the New England Journal of Medicine brings a bizarre problem to light: microbial stowaways in the topical products we use to sterilize things. Most drugs and infused fluids are prepared under sterile conditions. However, due to the antimicrobial activity of topical antiseptics, there is no requirement in the US that they be prepared in this way.

A number of cases of contamination have been reported over the years:

  • Iodophor – contamination with Buckholderia and Pseudomonas occurred during manufacture, leading to dialysis catheter infection and peritonitis
  • Chlorhexidine – contaminated with Serratia, Buckholderia and Ralstonia by end users, leading to wound infections, catheter infections, and death
  • Benzalkonium chloride – contaminated with Buckholderia and Mycobacteria by end users, causing septic arthritis and injection site infections

Bottom line: Nothing is sacred! This problem is scarier than you think, because our most basic assumptions about these products makes it nearly impossible for us to consider them when tracking down infection sources. Furthermore, they are so uncommon that they frequently may go undetected. The one telltale sign is the presence of infection from weird bacteria. If you encounter these bugs, consider this uncommon cause. Regulatory agencies need to get on this and mandate better manufacturing practices for topical antiseptics.

Reference: Microbial stowaways in topical antiseptic products. NEJM 367:2170-2173, Dec 6 2012.